just bought a capo, any suggestions on maintenance??

does it put extra pressure on the strings and increase the probability of breaking?

There really isn't a whole lot to consider when you're using the capo. Just don't leave it on the guitar for a few weeks without taking it off, then it'll crimp the strings (but that's not the end of the world either). I mean yeah, it makes everything tighter, but don't go changing your playing style drastically. Just play with it, worst case you break a string.
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